The relationship between the Anti-Saloon League and the Ku Klux Klan in support of national prohibition has been a source of controversy since the 1920s. Both the ASL and the KKK acted to enforce prohibition, the ASL through legal and political means, the KKK through grassroots political pressure and extralegal vigilante methods. Wet observers and, more recently, historians of the Klan movement claimed that the ASL cooperated with the Invisible Empire in direct enforcement of dry laws. ASL activists and prohibition historians, in turn, denied league involvement with the intolerant, occasionally violent, dry vigilantism of the Klan and instead stressed the nonpartisan bureaucratic operations of the ASL. The actual ambivalent relationship reflected shortcomings in the dry regime and in the two organizations. Ineffective enforcement pushed some ASL officials into informal ties with local Klans, while the league tolerated pro-Klan sentiments among some leaders. But extensive and persistent cooperation was not apparent.